Shop Windows to the Universe

How hot is the Sun, its surface and core? How long does it take the Sun's rays to reach the Earth?

A process called fusion heats the Sun. Fusion happens in the core of the Sun. It is very hot there. In fact, the core's average temperature is around 27,000,000 degrees Fahrenheit. The surface of the Sun is cool compared with the core, only 10,000 degrees Fahrenheit.

This fusion process not only heats the Sun, it makes the sunlight we see here on Earth. This sunlight travels the speed of light which is 186,282 miles per second or 299,792,458 meters per second. This means the light from the Sun takes 8.4 minutes to travel 93 million miles to Earth. If the world's fastest land animal were to travel that same distance, it would take a cheetah over 151 years to reach the Earth running about 70 mph nonstop!
Submitted by Jasmine (Minnesota, USA)
Submitted by Bobby (Quebec, Canada)
Submitted by John (Australia)
Submitted by Derek (Kansas, USA)
(September 22, 1997)

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